Unless you are from the United States, you will require either an eTA or Visa to enter Canada. In order to ascertain which you require check here http://www.cic.gc.ca/english/visit/index.asp
eTA (Electronic Travel Authorization)
– Required to fly to, or transit through Canada; no eta is required if you are travelling by land or sea.
– Cost is $7.00 CAD.
– The eTA authorizes the traveller to visit Canada for up to six months or until the date prescribed by a border services officer on arrival to Canada.
– Once you have an eTA, it will be valid for five years or until your passport expires, whichever comes first.
– It is good for multiple entries into Canada.
– To apply requires a valid passport, a credit card, an email address, and a few minutes of online time.
– Most applicants get approved within minutes. However, some may take several days and requests for additional documentation may occur so it's best to give lots of lead time.
– Notification is by email when the eTA is approved.
– The eTA is linked to the passport used in the eTA application. The traveler must present the passport used to apply for your eTA to airline staff each time they board a flight to Canada.
Canadian citizens, including dual citizens, and Canadian permanent residents cannot apply for an eTA.
For Travellers Requiring a Visa to Enter Canada
– Travellers with passports from visa-required countries and territories need a visitor visa (temporary resident visa) to enter Canada.
– Acquiring a Visa to Canada may take several weeks and even months
– A visa is an official document that is inserted inside a passport giving permission for you to come to Canada.
– There are two types: a single-entry visa and a multiple-entry visa. Both are valid for a fixed period and cannot be used after they expire.
– A multiple-entry visa allows visitors to come and go from Canada, usually for six months at a time, without having to reapply. It is valid for up to 10 years, or one month before your passport expires, whichever comes first. You must arrive in Canada on or before the expiry date on your visa.
– A single-entry visa allows you to come to Canada only once. After you leave Canada, excluding travel to the United States and St. Pierre and Miquelon, you will need a new visa to travel back to Canada.
Further information on applying for a Visa can be found here. http://www.cic.gc.ca/english/visit/apply-who.asp#visitorvisa
– Permanent residents (PRs) of Canada must carry and present their valid PR card or permanent resident travel document (PRTD) when boarding a flight to Canada, or travelling to Canada on any other commercial carrier. If you do not carry your PR card or PRTD, you may not be able to board your flight, train, bus or boat to Canada.
– It is your responsibility to ensure that your PR card is still valid when you return from travel outside Canada, and to apply for a new PR card when your current card expires. If your PR card expires, it does not mean you have lost permanent resident status.
Dual Canadian Citizens
– If you are a dual Canadian citizen used to travelling to or transiting through Canada by air with a non-Canadian passport, you will no longer be able to do so as of November 10, 2016. You will need a valid Canadian passport to board your flight.
– If your country needs you to enter and exit that country using a passport issued by its government, you will still need a valid Canadian passport to board your flight to Canada. Make sure to carry both passports when you travel.
– Exception: If you are an American-Canadian dual citizen with a valid U.S. passport, you don't need a Canadian passport to fly to Canada. However, you will still need to carry proper identification and meet the basic requirements to enter Canada.